An Unusual Leap
June 12, 2003
The life of a guillemot is not an easy one. Just a couple of weeks old, and these birds already have to leap from a cliff and fall more than 100 feet into the ocean.
Baby guillemots are no larger than a fist when they take this first major step. They are one of the few bird species that leave the nest before they are fully matured. And since they can't fly yet, it's a free fall to their first swim.
The youngsters then spend the next few weeks at sea with their father. By having them mature in the ocean, the adult bird can avoid the high-energy costs of transporting food from the ocean to the chick at the cliff. At about ten weeks, the little guillemots are fully fledged and begin their first flight exercises. They will only return to land when they themselves are adults and ready to breed.
Recognizing the young
Every June, around 2,000 guillemot couples come to the German island of Helgoland to breed. The birds don't build a nest, but rather lay one egg on a ledge in the appropriately-named "Guillemot Rock" on the island's western coast.The eggs have an unusual pear shape, which keeps them from rolling off even the narrowest of ledges.
A brown spotted pattern, which changes in the course of incubation, allows the adult guillemots to identify "their" baby. The little birds also develop an individual call already in the egg, which the parents later recognize.
Safety in numbers
Some baby guillemots fall into a crevice in the cliff after they jump and die. But most usually don't hurt themselves, as they are light as a feather.
This differentiates them from the lemming, a small, mouse-like rodent that on occasion leaps into the sea and drowns.
But the fledgling guillemots have a higher risk of death if they leap from their breeding cliffs alone. The usual strategy is to jump with everyone else, so that they are shielded from the predatory seagulls by other members of their cohort.